Gov. Andrew M. Cuomo’s ambition to develop enough offshore wind energy by 2030 to power 750,000 homes will require 280 square miles of ocean starting 12 to 15 miles from the Long Island shore, state officials said.

In a presentation to Long Island fishing groups in Setauket last week, state officials unveiled a map outlining a massive wind-study area south of Long Island that could result in three wind farms in the water over the next decade.

Greg Matzat, a senior adviser to the New York State Energy Research and Development Authority, which is leading the state effort, said each of three 800-megawatt wind farms could cost from $2 billion to $3 billion, and place 100 turbines in water no more than 200 feet deep.

One prospective array would sit off the coast of the entire South Fork. Though ultimate authority rests with the federal government, which leases the water rights, the state’s plan would envision turbines on some 237,000 acres of ocean. One megawatt of offshore wind power is enough to power 320 homes.

The sometimes testily received presentation came as LIPA also prepares to approve a 15-turbine wind farm off the coast of Rhode Island some 30 miles from Montauk Point. That project, when combined with other power initiatives and upgrades, would hike average residential customer bills by $3.67 a month when completed by 2026, LIPA has estimated. Trustees will vote on that project Wednesday, and its approval is widely expected.

For the projects directly off Long Island’s coast, turbines “would not be very big on the horizon,” said Gregory Lampman, senior project manager for the Energy Research and Development Authority.

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Potential conflicts with fishing uses are another matter, Lampman said. The state has begun collecting data on fishing uses for two potential wind-farm areas off Long Island to “minimize conflicts” with fishing, he said.

One commercial fisherman at Tuesday’s Setauket meeting noted the location of that proposed array largely was determined before the meeting..

“Why are we having outreach after the site lease is already sold?” said Mike Fogal, a Jones Inlet commercial fisherman.

Matzat said the state was working to “get ahead” of the process for the remaining two potential sites in waters off Long Island. “We want to try to do a better job to try to locate offshore wind so we can coexist,” with fishing and other ocean users, he said.

Turbines up to 700 feet tall for the total 2,400-megawatt project discussed at the Setauket meeting would be three-quarters of a mile apart, he said, and transmission cables would be buried six feet under the seabed. Generally, Matzat said, wind farm areas “will be open for fishing,” though it is unclear whether commercial boats that trawl the seabed could operate within those areas.

Fishing groups, including New England scallopers, have already filed a lawsuit seeking an injunction to stop development of the first New York-area wind farm, in a productive fishing area known as the New York Bight.

Though New York State doesn’t control the federal waters in which the wind farms will be placed, it can steer the process by controlling the power contracts any future developer would need to sell the power they produce. The state also belongs to a federal task force that will determine future sites, assuming President Donald Trump decides to continue aggressive Obama administration wind energy policies. The U.S. Department of the Interior’s Bureau of Ocean Energy Management is the lead agency.

The three New York-area sites for the 2,400-megawatt project are separate from a considerably smaller 15-turbine wind farm off Rhode Island that LIPA’s board of trustees is expected to vote on. That project, by Deepwater Wind, is due south of the Rhode Island coast between Block Island and Martha’s Vineyard, some 30 miles from Montauk Point.

Deepwater is proposing to LIPA a second array in that same area of 210 megawatts. Most construction jobs are likely to be Rhode Island-based, though Deepwater has said the projects could lead to “hundreds” of unspecified local jobs.

Matzat said the state was seeking to take an early lead in the placement and parameters of two future farms after bidding unsuccessfully for a site 12 miles from Jones Beach that is being developed by Norway-based Statoil. Those two potential sites would be slightly south and east of the Statoil location. New York’s attempt to win the bidding helped push the final lease price for Statoil to $42.5 million, a record high for such a lease. LIPA first proposed that wind farm with Con Edison and the New York Power Authority nearly a decade ago.

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A letter from the Long Island Commercial Fishing Association read at last Tuesday’s meeting in Setauket cited potential damage to the seabed , fish and sea mammals due to pile driving of the turbine structures and cable placement as reasons the state’s newly proposed projects should be rejected.

Matzat said techniques would be used to “minimize” noise and other impacts, and noted environmental groups already have expressed concerns about impacts to whales. Lampman said pre-construction efforts would include monitoring of whales and sea turtles, and extensive aerial surveys of wildlife and wind speeds.

The state is working to collect “actual usage data” by the fishing fleet to develop farms that “work around” key fishing areas, he said.

“We’re trying to fill in these maps . . . to minimize the conflicts,” Matzat said, adding the state wants to get a “handle on where the fishing is and how it changes seasonally,” to avoid those conflicts.